net/atm/resources.c

   1 /* net/atm/resources.c - Statically allocated resources */
   2
   3 /* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
   4
   5 /* Fixes
   6  * Arnaldo Carvalho de Melo <acme@conectiva.com.br>
   7  * 2002/01 - don't free the whole struct sock on sk->destruct time,
   8  *           use the default destruct function initialized by sock_init_data */
   9
  10 #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
  11
  12 #include <linux/ctype.h>
  13 #include <linux/string.h>
  14 #include <linux/atmdev.h>
  15 #include <linux/sonet.h>
  16 #include <linux/kernel.h> /* for barrier */
  17 #include <linux/module.h>
  18 #include <linux/bitops.h>
  19 #include <linux/capability.h>
  20 #include <linux/delay.h>
  21 #include <linux/mutex.h>
  22 #include <linux/slab.h>
  23
  24 #include <net/sock.h>    /* for struct sock */
  25
  26 #include "common.h"
  27 #include "resources.h"
  28 #include "addr.h"
  29
  30
  31 LIST_HEAD(atm_devs);
  32 DEFINE_MUTEX(atm_dev_mutex);
  33
  34 static struct atm_dev *__alloc_atm_dev(const char *type)
  35 {
  36         struct atm_dev *dev;
  37
  38         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
  39         if (!dev)
  40                 return NULL;
  41         dev->type = type;
  42         dev->signal = ATM_PHY_SIG_UNKNOWN;
  43         dev->link_rate = ATM_OC3_PCR;
  44         spin_lock_init(&dev->lock);
  45         INIT_LIST_HEAD(&dev->local);
  46         INIT_LIST_HEAD(&dev->lecs);
  47
  48         return dev;
  49 }
  50
  51 static struct atm_dev *__atm_dev_lookup(int number)
  52 {
  53         struct atm_dev *dev;
  54         struct list_head *p;
  55
  56         list_for_each(p, &atm_devs) {
  57                 dev = list_entry(p, struct atm_dev, dev_list);
  58                 if (dev->number == number) {
  59                         atm_dev_hold(dev);
  60                         return dev;
  61                 }
  62         }
  63         return NULL;
  64 }
  65
  66 struct atm_dev *atm_dev_lookup(int number)
  67 {
  68         struct atm_dev *dev;
  69
  70         mutex_lock(&atm_dev_mutex);
  71         dev = __atm_dev_lookup(number);
  72         mutex_unlock(&atm_dev_mutex);
  73         return dev;
  74 }
  75 EXPORT_SYMBOL(atm_dev_lookup);
  76
  77 struct atm_dev *atm_dev_register(const char *type, const struct atmdev_ops *ops,
  78                                  int number, unsigned long *flags)
  79 {
  80         struct atm_dev *dev, *inuse;
  81
  82         dev = __alloc_atm_dev(type);
  83         if (!dev) {
  84                 pr_err("no space for dev %s\n", type);
  85                 return NULL;
  86         }
  87         mutex_lock(&atm_dev_mutex);
  88         if (number != -1) {
  89                 inuse = __atm_dev_lookup(number);
  90                 if (inuse) {
  91                         atm_dev_put(inuse);
  92                         mutex_unlock(&atm_dev_mutex);
  93                         kfree(dev);
  94                         return NULL;
  95                 }
  96                 dev->number = number;
  97         } else {
  98                 dev->number = 0;
  99                 while ((inuse = __atm_dev_lookup(dev->number))) {
 100                         atm_dev_put(inuse);
 101                         dev->number++;
 102                 }
 103         }
 104
 105         dev->ops = ops;
 106         if (flags)
 107                 dev->flags = *flags;
 108         else
 109                 memset(&dev->flags, 0, sizeof(dev->flags));
 110         memset(&dev->stats, 0, sizeof(dev->stats));
 111         atomic_set(&dev->refcnt, 1);
 112
 113         if (atm_proc_dev_register(dev) < 0) {
 114                 pr_err("atm_proc_dev_register failed for dev %s\n", type);
 115                 goto out_fail;
 116         }
 117
 118         if (atm_register_sysfs(dev) < 0) {
 119                 pr_err("atm_register_sysfs failed for dev %s\n", type);
 120                 atm_proc_dev_deregister(dev);
 121                 goto out_fail;
 122         }
 123
 124         list_add_tail(&dev->dev_list, &atm_devs);
 125
 126 out:
 127         mutex_unlock(&atm_dev_mutex);
 128         return dev;
 129
 130 out_fail:
 131         kfree(dev);
 132         dev = NULL;
 133         goto out;
 134 }
 135 EXPORT_SYMBOL(atm_dev_register);
 136
 137 void atm_dev_deregister(struct atm_dev *dev)
 138 {
 139         BUG_ON(test_bit(ATM_DF_REMOVED, &dev->flags));
 140         set_bit(ATM_DF_REMOVED, &dev->flags);
 141
 142         /*
 143          * if we remove current device from atm_devs list, new device
 144          * with same number can appear, such we need deregister proc,
 145          * release async all vccs and remove them from vccs list too
 146          */
 147         mutex_lock(&atm_dev_mutex);
 148         list_del(&dev->dev_list);
 149         mutex_unlock(&atm_dev_mutex);
 150
 151         atm_dev_release_vccs(dev);
 152         atm_unregister_sysfs(dev);
 153         atm_proc_dev_deregister(dev);
 154
 155         atm_dev_put(dev);
 156 }
 157 EXPORT_SYMBOL(atm_dev_deregister);
 158
 159 static void copy_aal_stats(struct k_atm_aal_stats *from,
 160     struct atm_aal_stats *to)
 161 {
 162 #define __HANDLE_ITEM(i) to->i = atomic_read(&from->i)
 163         __AAL_STAT_ITEMS
 164 #undef __HANDLE_ITEM
 165 }
 166
 167 static void subtract_aal_stats(struct k_atm_aal_stats *from,
 168     struct atm_aal_stats *to)
 169 {
 170 #define __HANDLE_ITEM(i) atomic_sub(to->i, &from->i)
 171         __AAL_STAT_ITEMS
 172 #undef __HANDLE_ITEM
 173 }
 174
 175 static int fetch_stats(struct atm_dev *dev, struct atm_dev_stats __user *arg,
 176                        int zero)
 177 {
 178         struct atm_dev_stats tmp;
 179         int error = 0;
 180
 181         copy_aal_stats(&dev->stats.aal0, &tmp.aal0);
 182         copy_aal_stats(&dev->stats.aal34, &tmp.aal34);
 183         copy_aal_stats(&dev->stats.aal5, &tmp.aal5);
 184         if (arg)
 185                 error = copy_to_user(arg, &tmp, sizeof(tmp));
 186         if (zero && !error) {
 187                 subtract_aal_stats(&dev->stats.aal0, &tmp.aal0);
 188                 subtract_aal_stats(&dev->stats.aal34, &tmp.aal34);
 189                 subtract_aal_stats(&dev->stats.aal5, &tmp.aal5);
 190         }
 191         return error ? -EFAULT : 0;
 192 }
 193
 194 int atm_dev_ioctl(unsigned int cmd, void __user *arg, int compat)
 195 {
 196         void __user *buf;
 197         int error, len, number, size = 0;
 198         struct atm_dev *dev;
 199         struct list_head *p;
 200         int *tmp_buf, *tmp_p;
 201         int __user *sioc_len;
 202         int __user *iobuf_len;
 203
 204 #ifndef CONFIG_COMPAT
 205         compat = 0; /* Just so the compiler _knows_ */
 206 #endif
 207
 208         switch (cmd) {
 209         case ATM_GETNAMES:
 210                 if (compat) {
 211 #ifdef CONFIG_COMPAT
 212                         struct compat_atm_iobuf __user *ciobuf = arg;
 213                         compat_uptr_t cbuf;
 214                         iobuf_len = &ciobuf->length;
 215                         if (get_user(cbuf, &ciobuf->buffer))
 216                                 return -EFAULT;
 217                         buf = compat_ptr(cbuf);
 218 #endif
 219                 } else {
 220                         struct atm_iobuf __user *iobuf = arg;
 221                         iobuf_len = &iobuf->length;
 222                         if (get_user(buf, &iobuf->buffer))
 223                                 return -EFAULT;
 224                 }
 225                 if (get_user(len, iobuf_len))
 226                         return -EFAULT;
 227                 mutex_lock(&atm_dev_mutex);
 228                 list_for_each(p, &atm_devs)
 229                         size += sizeof(int);
 230                 if (size > len) {
 231                         mutex_unlock(&atm_dev_mutex);
 232                         return -E2BIG;
 233                 }
 234                 tmp_buf = kmalloc(size, GFP_ATOMIC);
 235                 if (!tmp_buf) {
 236                         mutex_unlock(&atm_dev_mutex);
 237                         return -ENOMEM;
 238                 }
 239                 tmp_p = tmp_buf;
 240                 list_for_each(p, &atm_devs) {
 241                         dev = list_entry(p, struct atm_dev, dev_list);
 242                         *tmp_p++ = dev->number;
 243                 }
 244                 mutex_unlock(&atm_dev_mutex);
 245                 error = ((copy_to_user(buf, tmp_buf, size)) ||
 246                          put_user(size, iobuf_len))
 247                         ? -EFAULT : 0;
 248                 kfree(tmp_buf);
 249                 return error;
 250         default:
 251                 break;
 252         }
 253
 254         if (compat) {
 255 #ifdef CONFIG_COMPAT
 256                 struct compat_atmif_sioc __user *csioc = arg;
 257                 compat_uptr_t carg;
 258
 259                 sioc_len = &csioc->length;
 260                 if (get_user(carg, &csioc->arg))
 261                         return -EFAULT;
 262                 buf = compat_ptr(carg);
 263
 264                 if (get_user(len, &csioc->length))
 265                         return -EFAULT;
 266                 if (get_user(number, &csioc->number))
 267                         return -EFAULT;
 268 #endif
 269         } else {
 270                 struct atmif_sioc __user *sioc = arg;
 271
 272                 sioc_len = &sioc->length;
 273                 if (get_user(buf, &sioc->arg))
 274                         return -EFAULT;
 275                 if (get_user(len, &sioc->length))
 276                         return -EFAULT;
 277                 if (get_user(number, &sioc->number))
 278                         return -EFAULT;
 279         }
 280
 281         dev = try_then_request_module(atm_dev_lookup(number), "atm-device-%d",
 282                                       number);
 283         if (!dev)
 284                 return -ENODEV;
 285
 286         switch (cmd) {
 287         case ATM_GETTYPE:
 288                 size = strlen(dev->type) + 1;
 289                 if (copy_to_user(buf, dev->type, size)) {
 290                         error = -EFAULT;
 291                         goto done;
 292                 }
 293                 break;
 294         case ATM_GETESI:
 295                 size = ESI_LEN;
 296                 if (copy_to_user(buf, dev->esi, size)) {
 297                         error = -EFAULT;
 298                         goto done;
 299                 }
 300                 break;
 301         case ATM_SETESI:
 302         {
 303                 int i;
 304
 305                 for (i = 0; i < ESI_LEN; i++)
 306                         if (dev->esi[i]) {
 307                                 error = -EEXIST;
 308                                 goto done;
 309                         }
 310         }
 311         /* fall through */
 312         case ATM_SETESIF:
 313         {
 314                 unsigned char esi[ESI_LEN];
 315
 316                 if (!capable(CAP_NET_ADMIN)) {
 317                         error = -EPERM;
 318                         goto done;
 319                 }
 320                 if (copy_from_user(esi, buf, ESI_LEN)) {
 321                         error = -EFAULT;
 322                         goto done;
 323                 }
 324                 memcpy(dev->esi, esi, ESI_LEN);
 325                 error =  ESI_LEN;
 326                 goto done;
 327         }
 328         case ATM_GETSTATZ:
 329                 if (!capable(CAP_NET_ADMIN)) {
 330                         error = -EPERM;
 331                         goto done;
 332                 }
 333                 /* fall through */
 334         case ATM_GETSTAT:
 335                 size = sizeof(struct atm_dev_stats);
 336                 error = fetch_stats(dev, buf, cmd == ATM_GETSTATZ);
 337                 if (error)
 338                         goto done;
 339                 break;
 340         case ATM_GETCIRANGE:
 341                 size = sizeof(struct atm_cirange);
 342                 if (copy_to_user(buf, &dev->ci_range, size)) {
 343                         error = -EFAULT;
 344                         goto done;
 345                 }
 346                 break;
 347         case ATM_GETLINKRATE:
 348                 size = sizeof(int);
 349                 if (copy_to_user(buf, &dev->link_rate, size)) {
 350                         error = -EFAULT;
 351                         goto done;
 352                 }
 353                 break;
 354         case ATM_RSTADDR:
 355                 if (!capable(CAP_NET_ADMIN)) {
 356                         error = -EPERM;
 357                         goto done;
 358                 }
 359                 atm_reset_addr(dev, ATM_ADDR_LOCAL);
 360                 break;
 361         case ATM_ADDADDR:
 362         case ATM_DELADDR:
 363         case ATM_ADDLECSADDR:
 364         case ATM_DELLECSADDR:
 365         {
 366                 struct sockaddr_atmsvc addr;
 367
 368                 if (!capable(CAP_NET_ADMIN)) {
 369                         error = -EPERM;
 370                         goto done;
 371                 }
 372
 373                 if (copy_from_user(&addr, buf, sizeof(addr))) {
 374                         error = -EFAULT;
 375                         goto done;
 376                 }
 377                 if (cmd == ATM_ADDADDR || cmd == ATM_ADDLECSADDR)
 378                         error = atm_add_addr(dev, &addr,
 379                                              (cmd == ATM_ADDADDR ?
 380                                               ATM_ADDR_LOCAL : ATM_ADDR_LECS));
 381                 else
 382                         error = atm_del_addr(dev, &addr,
 383                                              (cmd == ATM_DELADDR ?
 384                                               ATM_ADDR_LOCAL : ATM_ADDR_LECS));
 385                 goto done;
 386         }
 387         case ATM_GETADDR:
 388         case ATM_GETLECSADDR:
 389                 error = atm_get_addr(dev, buf, len,
 390                                      (cmd == ATM_GETADDR ?
 391                                       ATM_ADDR_LOCAL : ATM_ADDR_LECS));
 392                 if (error < 0)
 393                         goto done;
 394                 size = error;
 395                 /* may return 0, but later on size == 0 means "don't
 396                    write the length" */
 397                 error = put_user(size, sioc_len) ? -EFAULT : 0;
 398                 goto done;
 399         case ATM_SETLOOP:
 400                 if (__ATM_LM_XTRMT((int) (unsigned long) buf) &&
 401                     __ATM_LM_XTLOC((int) (unsigned long) buf) >
 402                     __ATM_LM_XTRMT((int) (unsigned long) buf)) {
 403                         error = -EINVAL;
 404                         goto done;
 405                 }
 406                 /* fall through */
 407         case ATM_SETCIRANGE:
 408         case SONET_GETSTATZ:
 409         case SONET_SETDIAG:
 410         case SONET_CLRDIAG:
 411         case SONET_SETFRAMING:
 412                 if (!capable(CAP_NET_ADMIN)) {
 413                         error = -EPERM;
 414                         goto done;
 415                 }
 416                 /* fall through */
 417         default:
 418                 if (compat) {
 419 #ifdef CONFIG_COMPAT
 420                         if (!dev->ops->compat_ioctl) {
 421                                 error = -EINVAL;
 422                                 goto done;
 423                         }
 424                         size = dev->ops->compat_ioctl(dev, cmd, buf);
 425 #endif
 426                 } else {
 427                         if (!dev->ops->ioctl) {
 428                                 error = -EINVAL;
 429                                 goto done;
 430                         }
 431                         size = dev->ops->ioctl(dev, cmd, buf);
 432                 }
 433                 if (size < 0) {
 434                         error = (size == -ENOIOCTLCMD ? -EINVAL : size);
 435                         goto done;
 436                 }
 437         }
 438
 439         if (size)
 440                 error = put_user(size, sioc_len) ? -EFAULT : 0;
 441         else
 442                 error = 0;
 443 done:
 444         atm_dev_put(dev);
 445         return error;
 446 }
 447
 448 void *atm_dev_seq_start(struct seq_file *seq, loff_t *pos)
 449 {
 450         mutex_lock(&atm_dev_mutex);
 451         return seq_list_start_head(&atm_devs, *pos);
 452 }
 453
 454 void atm_dev_seq_stop(struct seq_file *seq, void *v)
 455 {
 456         mutex_unlock(&atm_dev_mutex);
 457 }
 458
 459 void *atm_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 460 {
 461         return seq_list_next(v, &atm_devs, pos);
 462 }